Senior iOS Engineer

Octopus Energy started with a bold idea: to build Britain’s first truly digital energy supplier. By combining world‑class tech with brilliant humans who care deeply about customers and driving the renewable energy transition, we made it happen and in 2025, we became Britain’s largest energy supplier. Now, we’re scaling fast and building the next generation of products to accelerate the green energy transition. From making it effortless to switch to heat pumps, solar and EVs, to launching smart tariffs and creating renewable generation at scale, we’re solving some of the most complex challenges in energy with speed, creativity and customer obsession.

We’re also enabling our global businesses to reach the full capability of what we’ve achieved in the UK, taking the learnings, products and experiences that customers love here and rolling them out worldwide. At Octopus Tech, you’ll have real ownership, variety, and the chance to shape products that make a tangible difference in people’s lives - lowering bills, enabling greener living, and delivering experiences customers genuinely love. You’ll work side by side with teams across marketing, operations, and data, and see the impact of your work in the real world, fast.

The flexibility team is building the next generation of products and tools to make energy more flexible. These include our flagship Intelligent Octopus product automating demand shift for 300,000 customers with electric cars, home batteries or smart heating devices, saving 2 million customers money through Saving Sessions and Free Electricity Sessions, and managing 568MW of large grid‑scale batteries to balance the system. The team develops products that are used by millions of customers, helping boost renewables use and decarbonise energy systems worldwide.

As an organisation we like to move quickly. This is true both in how we operate as a business and the technology choices we make. We were very early adopters of Kotlin Multiplatform (KMP) and used the technology when it was in pre‑alpha, at scale, to great success. It helps us share code across Android and iOS without the user experience tradeoffs. KMP was officially released in late 2023 so we don’t expect our applicants to have experience using it. It powers the extensive shared layer across our Android and iOS apps, with UI powered by Jetpack Compose and SwiftUI. Our app is built around offline‑first reactive patterns and utilises unidirectional data flow with a layered architecture. Our view models are written using Jetpack Compose and compliment our state driven UI. We release updates to customers weekly. We gain release confidence with our suite of automation and unit tests running in CI (GitHub Actions), and configure features remotely using feature flags.

You’ll be someone who appreciates the impact a nimble team can make on customers and clean energy. Your passion for clean energy and sustainability will help provide context on your everyday work. You will thrive with us if you can effectively communicate with coworkers in different timezones. You’ll enjoy contributing across the whole development process including design and product. Finally, you’re interested in staying on top of upcoming technologies that could benefit our team. We’re looking to hire someone with 4+ years of experience with Kotlin or Swift.

We embrace flat hierarchies and an open, agile culture that fosters innovation, flexibility, and creativity. We don’t hang our personalities up with our coats and nor should you. At Octopus, we hire great people who get stuff done, all whilst being themselves.

If this sounds exciting, we’d love to chat.

Why else you’ll love it here... Wondering what the salary for this role is? Just ask us! On a call with one of our recruiters it’s something we always cover as we genuinely want to match your experience with the correct salary. The reason why we don’t advertise is because we honestly have a degree of flexibility and would never want salary to be a reason why someone doesn’t apply to Octopus - what’s more important to us is finding the right octofit!

Octopus Energy Group is a unique culture. An organisation where people learn, decide, and build quicker. Where people work with autonomy, alongside a wide range of amazing co-owners, on projects that break new ground. We want your hard work to be rewarded with perks you actually care about! We won best company to work for in 2022, on Glassdoor we were voted 50 best places to work in 2022 and our Group CEO, Greg has recorded a podcast about our culture and how we empower our people. We’ve also been placed in the top 10 companies for senior leadership.

Our process usually takes up to 4 weeks, but we’ll always do our best to flex around what works for you. Along the way, you’ll chat with our recruitment team and your Recruiter will help you throughout different stages. Got any burning questions before then? Drop us a message at hiring@octoenergy.com and we’d love to help!

If this sounds like you then we’d love to hear from you. Are you ready for a career with us? We want to ensure you have all the tools and environment you need to unleash your potential. Need any specific accommodations? Whether you require specific accommodations or have a unique preference, let us know, and we’ll do what we can to customise your interview process for comfort and maximum magic!

Studies have shown that some groups of people, like women, are less likely to apply to a role unless they meet 100% of the job requirements. Whoever you are, if you like one of our jobs, we encourage you to apply as you might just be the candidate we hire. Across Octopus, we’re looking for genuinely decent people who are honest and empathetic. Our people are our strongest asset and the unique skills and perspectives people bring to the team are the driving force of our success. As an equal opportunity employer, we do not discriminate on the basis of any protected attribute. Our commitment is to provide equal opportunities, an inclusive work environment, and fairness for everyone.